Lujo Bauer Scott Garriss Michael K. Reiter Efficient Proving for Practical Distributed Access-Control Systems. 19-37 2007 conf/esorics/2007 ESORICS http://dx.doi.org/10.1007/978-3-540-74835-9_3 db/conf/esorics/esorics2007.html#BauerGR07